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Altera_Forum's avatar
Altera_Forum
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15 years ago

ow to define an uncached linker region

Can anyone tell me how to define a region in the linker to be uncached? An example - I have a block ram I am using for SGDMA descriptor tables that I need to define as uncached... Thanks - Chris
Altera_Forum's avatar
Altera_Forum
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15 years ago

you don't need to avoid IDE for this one. For ALL of my memory mapped SOPC components, I declaire a pointer to my HW\memories in C code like this:

#define data_cache_bypass_mask 0x80000000

volatile alt_u32 * uart_pointer = (volatile alt_u32*)(avalon_uart_0_base|data_cache_bypass_mask);

then you can access your block\memory like

uart_pointer[0] = 0xDEADBEEF;

and the datacache bypass mask is already applied by the compiler.